This is a revised set of patches following helpful feedback. There are now more patches, but they should be a lot easier to review. These patches are all in a git tree at https://github.com/neilbrown/linux/commits/pdirops though there a lot more patches there too - demonstrating what is to come. 0eaa1c629788 ovl: rename ovl_cleanup_unlocked() to ovl_cleanup() is the last in the series posted here. I welcome further review. Original description: This series of patches for overlayfs is primarily focussed on preparing for some proposed changes to directory locking. In the new scheme we will lock individual dentries in a directory rather than the whole directory. ovl currently will sometimes lock a directory on the upper filesystem and do a few different things while holding the lock. This is incompatible with the new scheme. This series narrows the region of code protected by the directory lock, taking it multiple times when necessary. This theoretically open up the possibilty of other changes happening on the upper filesytem between the unlock and the lock. To some extent the patches guard against that by checking the dentries still have the expect parent after retaking the lock. In general, I think ovl would have trouble if upperfs were being changed independantly, and I don't think the changes here increase the problem in any important way. I have tested this with fstests, both generic and unionfs tests. I wouldn't be surprised if I missed something though, so please review carefully. After this series (with any needed changes) lands I will resubmit my change to vfs_rmdir() behaviour to have it drop the lock on error. ovl will be much better positioned to handle that change. It will come with the new "lookup_and_lock" API that I am proposing. Thanks, NeilBrown [PATCH 01/20] ovl: simplify an error path in ovl_copy_up_workdir() [PATCH 02/20] ovl: change ovl_create_index() to take write and dir [PATCH 03/20] ovl: Call ovl_create_temp() without lock held. [PATCH 04/20] ovl: narrow the locked region in ovl_copy_up_workdir() [PATCH 05/20] ovl: narrow locking in ovl_create_upper() [PATCH 06/20] ovl: narrow locking in ovl_clear_empty() [PATCH 07/20] ovl: narrow locking in ovl_create_over_whiteout() [PATCH 08/20] ovl: narrow locking in ovl_rename() [PATCH 09/20] ovl: narrow locking in ovl_cleanup_whiteouts() [PATCH 10/20] ovl: narrow locking in ovl_cleanup_index() [PATCH 11/20] ovl: narrow locking in ovl_workdir_create() [PATCH 12/20] ovl: narrow locking in ovl_indexdir_cleanup() [PATCH 13/20] ovl: narrow locking in ovl_workdir_cleanup_recurse() [PATCH 14/20] ovl: change ovl_workdir_cleanup() to take dir lock as [PATCH 15/20] ovl: narrow locking on ovl_remove_and_whiteout() [PATCH 16/20] ovl: change ovl_cleanup_and_whiteout() to take rename [PATCH 17/20] ovl: narrow locking in ovl_whiteout() [PATCH 18/20] ovl: narrow locking in ovl_check_rename_whiteout() [PATCH 19/20] ovl: change ovl_create_real() to receive dentry parent [PATCH 20/20] ovl: rename ovl_cleanup_unlocked() to ovl_cleanup()
